This invention relates to a receptacle-type optical connector adapted to be mounted to various kinds of apparatuses in the field of optical communication.
For example, Japanese Patent (JP-B) No. 3424172 (corresp. to U.S. Pat. No. 6,361,218 B1) discloses an optical connector module comprising a plug-type optical connector and a receptacle-type optical connector coupled with each other. For example, Japanese Patent Application Publication (JP-A) No. 2001-183549 discloses an optical connector in which an optical connection loss is reduced by suppressing displacement or misalignment of a ferule inserted into a sleeve.
As one of important features of an optical apparatus, an optical fiber connected to the apparatus and light emitting and light receiving elements in the apparatus must be arranged without axial displacement or misalignment therebetween so that optical energy can be coupled and transmitted without a connection loss. Therefore, a positional relationship between the optical fiber and the light emitting and the light receiving elements upon coupling is required to be reproducible with high accuracy.
The plug-type optical connector may use a ferrule having a relatively large diameter (for example, 2.5 mm) and a ferrule having a relatively small diameter (for example, 1.25 mm) intended to achieve space saving. In this connection, the receptacle-type optical connector is also required to be adapted to those ferrules different in diameter.